The mass accretion rate of galaxy clusters: a measurable quantity

Abstract

We explore the possibility of measuring the mass accretion rate (MAR) of galaxy clusters from their mass profiles beyond the virial radius $R_{200}$. We derive the accretion rate from the mass of a spherical shell whose inner radius is $2R_{200}$, whose thickness changes with redshift, and whose infall velocity is assumed to be equal to the mean infall velocity of the spherical shells of dark matter halos extracted from $N$-body simulations. This approximation is rather crude in hierarchical clustering scenarios where both smooth accretion and aggregation of smaller dark matter halos contribute to the mass accretion of clusters.Nevertheless, in the redshift range $z=[0,2]$, our prescription returns an average MAR within $20-40\%$ of the average rate derived from the merger trees of dark matter halos extracted from $N$-body simulations. The MAR of galaxy clusters has been the topic of numerous detailed numerical and theoretical investigations, but so far it has remained inaccessible to measurements in the real universe. Since the measurement of the mass profile of clusters beyond their virial radius can be performed with the caustic technique applied to dense redshift surveys of the cluster outer regions, our result suggests that measuring the mean MAR of a sample of galaxy clusters is actually feasible. We thus provide a new potential observational test of the cosmological and structure formation models.

11 pages, 7 figures, 5 tables, minor text modifications to match the published version, typos corrected

References in corpus (11)

• Rotation-Dependent Catastrophic Disruption of Gravitational Aggregates
• The splashback radius as a physical halo boundary and the growth of halo mass
• CIRS: Cluster Infall Regions in the Sloan Digital Sky Survey I. Infall Patterns and Mass Profiles
• The Nearly Universal Merger Rate of Dark Matter Haloes in Lambda-CDM Cosmology
• Galaxy growth in the concordance $\Lambda$CDM cosmology
• Splashback in accreting dark matter halos
• The pseudo-evolution of halo mass
• The accretion history of dark matter halos II: The connections with the mass power spectrum and the density profile
• Galaxy And Mass Assembly (GAMA): Refining the Local Galaxy Merger Rate using Morphological Information
• An improved model for the formation times of dark matter haloes
• Coming of Age in the Dark Sector: How Dark Matter Haloes grow their Gravitational Potential Wells

Cited by in corpus (20)

• Turbulent pressure support and hydrostatic mass-bias in the intracluster medium
• LoCuSS: The infall of X-ray groups onto massive clusters
• Can giant radio halos probe the merging rate of galaxy clusters?
• First detection of a virial shock with SZ data: implication for the mass accretion rate of Abell 2319
• Fast Weak Lensing Simulations with Halo Model
• The Massively Accreting Cluster A2029
• Mass accretion rates of clusters of galaxies: CIRS and HeCS
• HectoMAP: The Complete Redshift Survey (Data Release 2)
• Blooming Trees: Substructures and Surrounding Groups of Galaxy Clusters
• The Co-Evolution of a Magnetized Intracluster Medium and Hot Galactic Coronae: Magnetic Field Amplification and Turbulence Generation
• The Velocity Dispersion Function for Quiescent Galaxies in Nine Strong-Lensing Clusters
• Galaxy cluster mass accretion rates from IllustrisTNG
• An IllustrisTNG View of the Caustic Technique for Galaxy Cluster Mass Estimation
• Scatter in the satellite galaxy SHMR: fitting functions, scaling relations & physical processes from the IllustrisTNG simulation
• Mass accretion rates of the HectoMAP clusters of galaxies
• IllustrisTNG Snapshots for 10 Gyr of Dynamical Evolution of Brightest Cluster Galaxies and Their Host Clusters
• Modelling the mass accretion histories of dark matter haloes using a Gamma formalism
• Testing the Reliability of Fast Methods for Weak Lensing Simulations: WL-MOKA on PINOCCHIO
• The eventful life journey of galaxy clusters. I. Impact of DM halo and ICM properties on their full assembly histories
• The Pseudo Evolution of Galaxy-Cluster Masses and Its Connection to Mass Density Profile